Help: hash-policy

The "hash-policy" command:

Usage: fossil hash-policy ?NEW-POLICY?
Query or set the hash policy for the current repository. Available hash
policies are as follows:
sha1 New artifact names are created using SHA1
auto New artifact names are created using SHA1, but
automatically change the policy to "sha3" when
any SHA3 artifact enters the repository.
sha3 New artifact names are created using SHA3, but
older artifacts with SHA1 names may be reused.
sha3-only Use only SHA3 artifact names. Do not reuse legacy
SHA1 names.
shun-sha1 Shun any SHA1 artifacts received by sync operations
other than clones. Older legacy SHA1 artifacts are
allowed during a clone.
The default hash policy for existing repositories is "auto", which will
immediately promote to "sha3" if the repository contains one or more
artifacts with SHA3 names. The default hash policy for new repositories
is "shun-sha1".